Re: [PATCH] cache-tree: reject entries with null sha1

From: Duy Nguyen <pclouds@gmail.com>
Date: May 3, 2017, 09:46 UTC
Message-ID: <CACsJy8CdjLySD+UEKE2NkbYqEoVOQtvydFBui6UbbnFLo8U1Ug@mail.gmail.com>
In-Reply-To: <20170501192212.xy5o72tinb2hy2a3@sigill.intra.peff.net>

On Tue, May 2, 2017 at 2:22 AM, Jeff King <peff@peff.net> wrote:

Show 27 quoted lines

> On Mon, May 01, 2017 at 01:23:28PM +0200, René Scharfe wrote:
>
>> Am 24.04.2017 um 12:39 schrieb Duy Nguyen:
>> > BTW, I ran t7009 with valgrind and it reported this. Is it something
>> > we should be worried about? I vaguely recall you're doing something
>> > with prio-queue...
>> >
>> > ==4246== Source and destination overlap in memcpy(0x5952990, 0x5952990, 16)
>> > ==4246==    at 0x4C2EACD: memcpy@@GLIBC_2.14 (in
>> > /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
>> > ==4246==    by 0x545D05: swap (prio-queue.c:15)
>> > ==4246==    by 0x545D72: prio_queue_reverse (prio-queue.c:25)
>> > ==4246==    by 0x4CBC0C: sort_in_topological_order (commit.c:723)
>> > ==4246==    by 0x574C97: prepare_revision_walk (revision.c:2858)
>> > ==4246==    by 0x48A2BA: cmd_rev_list (rev-list.c:385)
>> > ==4246==    by 0x405A6F: run_builtin (git.c:371)
>> > ==4246==    by 0x405CDC: handle_builtin (git.c:572)
>> > ==4246==    by 0x405E51: run_argv (git.c:624)
>> > ==4246==    by 0x405FF3: cmd_main (git.c:701)
>> > ==4246==    by 0x4A48CE: main (common-main.c:43)
>>
>> I can only get gcc and clang to call memcpy instead of inlining it by
>> specifying -fno-builtin.  Do you use that option?  If yes, why?  (Just
>> curious.)
>
> I do my normal edit-compile cycles with -O0 because it's fast, and
> because it makes debugging much easier.

Same here. My CFLAGS (without lots of -Wstuff)

CFLAGS =  -g -O0 -fstack-protector

Maybe it's -fstack-protector then? This is gcc 4.9.3. I think Gentoo does not add any distro-specific patches on this particular version.

-- 
Duy